He said CEOP had received 252 complaints about Facebook in the first three months of this year, compared to 297 in the whole of 2009, according to reports.

Gamble has been campaigning for several months for Facebook, increasingly the dominant social network, to agree to publish a CEOP-branded panic button. It has steadfastly refused, arguing its own reporting procedures are effective, and rejecting calls from the Home Secretary to comply with CEOP's demands.

Gamble said: "None [of the 252 reports received this year by CEOP] came direct from Facebook. If their system is so robust and they are receiving so many reports and concerns from young people, then where are they?"

The panic button sends users to a CEOP page containing advice on everyday internet security threats and bullying, inappropriate content, as well as a link to report suspicious approaches to investigators.

"Is Facebook so arrogant that it does not matter what the collective child protection community think?" Gamble said in a briefing with reporters.

"Do they want to be the website of choice for bullies, for dangerous individuals, for rapists and murderers?"

The latest attack comes ahead of a meeting between CEOP and Facebook in Washington DC next week. So far, Microsoft and Bebo have agreed to publish the button, although this week it was revealed that AOL is likely to shut down the latter because it has proved a commercial failure.

The media pressure on Facebook from CEOP has been extreme this year, with Gamble taking to the airwaves immediately after the conviction of Ashleigh Hall's killer.

It seems very unlikely that she would have been helped by CEOP's panic button however. The 17-year-old naively agreed to a real world meeting with a Facebook friend, believing he was a teenage boy. In fact he was 33-year-old convicted sex offender Peter Chapman, who the police had lost track of.

News Corp-owned social network MySpace, which has a high proportion of teenagers among its user base compared to Facebook, has not been subject to the same intense public criticism from CEOP, although it has so far also declined to publish the panic button. ®